AIM: Hypothermia is a recognized complication of severe hypoglycaemia, but its prevalence and characteristics are poorly studied. For this reason, this study aimed to evaluate hypothermia in severely hypoglycaemic patients. METHODS: A retrospective chart review was performed including all patients discharged between 2007 and 2010 from the Emergency Department of the Geneva University Hospital with a diagnosis of severe hypoglycaemia. RESULTS: Hypothermia was identified in 30 (23.4%) out of 128 patients with severe hypoglycaemia. Its incidence was not affected by age, type of diabetes, season or time of day (day/night). Using linear regression, the lowest recorded temperature was associated with the Glasgow Coma Scale (GCS) score (r2=13.8%, P<0.0001) and inversely associated with the leukocyte count (r2=13.1%, P=0.001). CONCLUSION: Hypothermia is a frequent sign of severe hypoglycaemia in patients with diabetes. The associations between hypothermia and the GCS score and the leukocyte count suggest that it is a marker of hypoglycaemia severity and/or duration. Hypothermia may represent an important compensatory mechanism in severe hypoglycaemia, reflecting a decrease in energy demand during glucose deprivation.